Issue 68

H. Mostafa et alii, Frattura ed Integrità Strutturale, 68 (2024) 19-44; DOI: 10.3221/IGF-ESIS.68.02

Furthermore, varying the spacing of molded gratings presents an intriguing area for exploration. Modifying the spacing between gratings may influence the structural behavior and load-carrying capacity of RC flat slabs. A systematic study on the impact of different grating spacings on punching shear resistance could lead to recommendations for optimal spacing configurations. This study enables designers to tailor reinforcement strategies based on specific project requirements. Additionally, investigating the use of pultruded gratings as a reinforcement system represents an avenue for future research. Pultruded gratings, known for their high strength and durability, could offer distinct mechanical properties compared to molded gratings. An examination of their performance in punching shear resistance in RC flat slabs under various loading conditions would provide valuable data for engineers and researchers seeking optimal FRP reinforcement solutions. [1] Swamy, R. N., and Ali, S. A. R. (1982). Punching shear behavior of reinforced slab-column connections made with steel fiber concrete. ACI Structural Journal, 79(5), pp. 392-406. DOI: 10.14359/10917. [2] Ospina, C. E., Alexander, S. D. B., and Cheng, J. J. R. (2003). Punching of two-way concrete slabs with fiber-reinforced polymer reinforcing bars or grids. ACI Structural Journal, (100) 5, pp. 589-598. DOI: 10.14359/12800. [3] Mu, B., and Meyer, C. (2003). Bending and punching the shear strength of fiber-reinforced glass concrete slabs. ACI Structural Journal, (100)2, pp. 127-132. DOI: 10.14359/12552. [4] Zhang, B., Masmoudi, R., and Benmokrane, B. (2004). The behavior of one-way concrete slabs reinforced with CFRP grid reinforcements. Construction and Building Materials, 18, pp. 625-635. DOI: 10.1016/j.conbuildmat.2004.04.007. [5] Dimitrios, D., Theodorakopoulos, H., and Swamy, N. (2007). Analytical model to predict punching shear strength of FRP-reinforced concrete flat slabs. ACI Structural Journal, (104), 3, pp. 257-266. DOI: 10.14359/18615. [6] Esfahani, M. R., Kianoush, M. R., and Moradi, A. R. (2007). Punching shear strength of interior slab column connections strengthened with carbon fiber-reinforced polymer sheets. Engineering Structures, (31) 7, pp. 1535-1542. DOI: 10.1016/j.engstruct.2009.02.021. [7] Stuart, V., and Cunningham, L.S. (2017). FRP-reinforced concrete slabs: A comparative design study. Proceedings of the Institution of Civil Engineers Structures and Buildings, (170) 8, pp. 581-602. DOI:10.1680/jstbu.16.00055 [8] Abdulrahman B. Q., Wu Z., and Cunningham L. S. (2017). Experimental and numerical investigation into strengthening flat slabs at corner columns with externally bonded CFRP. Construction and Building Materials, (139), pp. 132-147. DOI: 10.1016/j.conbuildmat.2017.02.056 [9] Hemzah, S. A., Al-Obaidi, S., and Salim, T. (2019). Punching shear model for normal and high-strength concrete slabs reinforced with CFRP or steel bars. Jordan Journal of Civil Engineering, (13) 2, pp. 250-268. [10] Said, M., Adam, M.A., Arafa, A.E., and Moatasem, A. (2020). Improvement of the punching shear strength of reinforced lightweight concrete flat slabs using different strengthening techniques. Journal of Building Engineering, 32, 101749. DOI: 10.1016/j.jobe.2020.101749. [11] Kim, M. S., and Lee, Y. H. (2021). Punching the shear strength of reinforced concrete flat plates with GFRP vertical grids. Applied Sciences, (11) 6, DOI: 10.3390/app11062736. [12] Bank, L.C., Xi, Z., and Munley, E. (1992). Tests of full-size pultruded FRP gratings reinforced concrete bridge decks. Conference Proceedings of ASCE, Materials Engineering Congress, New York, pp. 618-631. [13] Bank, L.C., Frostig, Y., and A. Shapira (1997). Three-dimensional FRP grating cages for concrete beams. ACI Structural Journal, (94) 6, pp. 643-652. DOI: 10.14359/9724. [14] Biddah A., (2006). Structural reinforcement of bridge decks using pultruded GFRP gratings. Composite Structures, 74, pp. 80-88. DOI: 10.1016/j.compstruct.2005.03.016. [15] Devender, B., Purushotham, A. and Reddy, V. (2013). Experimental tests on GFRP gratings were constructed for mechanical properties and chemical resistance. IOSR Journal of Mechanical and Civil Engineering, (8) 6, pp. 34-39. [16] Gattesco, N., Dilena, M., and Boem, I. (2019). Experimental and numerical study on the bending performances of glass FRP-molded gratings. Influence of restraining conditions and cover plates, Composite Structures, 223, p. 110967. DOI: 10.1016/j.compstruct.2019.110967. [17] ECP Committee (2018). Egyptian Code for Design and Construction of Concrete Structures (ECP 203-2018). Housing and Building National Research Center, Cairo, Egypt. [18] ACI Committee 318 (2020). Building Code Requirements for Structural Concrete (ACI 318-19). An ACI Standard, Commentary on Building Code Requirements for Structural Concrete (ACI 318R-19), American Concrete Institute. [19] ASTM, A370-17 (2006). 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